- Sanofi reveals dengue vaccine unsafe for people not previously infected
- Second infection with virus can be severe especially for immunised kids
- Philippines to monitor 492,000 schoolchildren immunised last year
[MANILA] Warnings by the pharmaceutical firm Sanofi Pasteur that its dengue vaccine is unsafe for people who have never been infected with the dengue virus has Philippine officials scrambling to contain the backlash on a decision to roll out the vaccine.
In a statement last Thursday (29 November), Sanofi said Dengvaxia, the first ever dengue vaccine, could put people at risk of “severe disease” if they had not previously been infected with the virus. Dengvaxia, the statement said, provides “persistent protective benefit against dengue fever” for those who have had prior infection.
There are four dengue strains and a first infection with any one of them is usually mild. A second infection with a different strain can result in severe disease and the vaccine apparently mimics a first infection.
“The government will actively monitor all immunised children for at least five years,”
Francisco Duque III
Of the 11 countries which approved commercial release of the vaccine, only the Philippines (over 700,000 vaccinated) and the Parana state of Brazil (about 300,000 vaccinated) had mass vaccination programmes.